The present study was carried out on the newly formed pupae of the house fly Musca domestica L. (... more The present study was carried out on the newly formed pupae of the house fly Musca domestica L. (Diptera: Muscidae) to determine some biological effects of different doses of thermal neutrons. The tested pupae were subjected to 2.4 x 10 5 , 4.86 x 10 5 and9.72 x 10 5 (neutron/cm 2-S) thermal neutrons/pupa for 24 hours and to 4.86 x 10 5 , 9.72 x 10 5 and19.2 x 10 5 (neutron/cm 2-S) thermal neutrons/pupa for 48 hours. After treatment, the pupae were transferred to the rearing cages to determine any possible effects on them or on the resulting adults. There was a positive correlation between the dose level and the pupal duration, where the increase of the dose level increases the pupal duration and decreases the developmental rate. No influence on the adult emergence was detected. With increasing doses the preoviposition period increases. On the other hand, this increase decreases the oviposition period and causes a slight increase in the post oviposition period irrespective of the exposure time. A positive correlation was observed between the low doses and the fecundity, due to gonads activation, while this relationship was found to be negative at the highest dose, where it reduces it to 220 eggs/♀ and 311.6 eggs/♀ after exposure time of 24 and 48 hours, respectively compared with 370.6 eggs/♀ for control congeners. Positive fecundity inhibition percentage values were recorded at low doses. Females exposed to the highest dose showed negative responses, irrespective of the period of treatment. The fertility was also found to be slightly affected, where it declined (88.4 and 83.5 vs. 95.8 % for control) for females treated with the higher doses (9.72X10 5 and 19.2 x 10 5) for 24 and 48 hours, respectively. Finally, the sterility index had been calculated and proved the detrimental effects of the mid and high doses on the egg hatchability.
This investigation documents the presence of the alien macroalgal species Rivularia atra Roth ex ... more This investigation documents the presence of the alien macroalgal species Rivularia atra Roth ex Bornet & Flahault (Rivulariaceae: Nostocales) and Polysiphonia opaca (C. Agardh) Moris & De Notaris (Rhodomelaceae: Ceramiales) for the first time on the Libyan coastline. Of 7 investigated sites along Al-Jabel Al-Akhdar coastline during summer 2013 and winter 2014, three sites were invaded by R. atra and one site by P. opaca. The percent cover and relative frequency – as measures of abundance-of R. atra (15-24% and 40-70% respectively) were higher than those of P. opaca (8% and 17 % respectively). The investigation revealed that R. atra and P. opaca inhabited not only the rocky substrates but also the limpet Patella caerulea and that the two species do not thrive in polluted habitats. Statistical analysis showed a highly significant effect of season, site and their interaction on the physico-chemical characteristics of water. The results concluded that the nature of substrate as well as the extent of pollution may be major modifiers of algal distribution, since the non-polluted bare rocky shore was the favorite habitat for the alien species R. atra and P. opaca. Therefore, these species are promising indicators for water quality.
The present study was carried out on the newly formed pupae of the house fly Musca domestica L. (... more The present study was carried out on the newly formed pupae of the house fly Musca domestica L. (Diptera: Muscidae) to determine some biological effects of different doses of thermal neutrons. The tested pupae were subjected to 2.4 x 10 5 , 4.86 x 10 5 and9.72 x 10 5 (neutron/cm 2-S) thermal neutrons/pupa for 24 hours and to 4.86 x 10 5 , 9.72 x 10 5 and19.2 x 10 5 (neutron/cm 2-S) thermal neutrons/pupa for 48 hours. After treatment, the pupae were transferred to the rearing cages to determine any possible effects on them or on the resulting adults. There was a positive correlation between the dose level and the pupal duration, where the increase of the dose level increases the pupal duration and decreases the developmental rate. No influence on the adult emergence was detected. With increasing doses the preoviposition period increases. On the other hand, this increase decreases the oviposition period and causes a slight increase in the post oviposition period irrespective of the exposure time. A positive correlation was observed between the low doses and the fecundity, due to gonads activation, while this relationship was found to be negative at the highest dose, where it reduces it to 220 eggs/♀ and 311.6 eggs/♀ after exposure time of 24 and 48 hours, respectively compared with 370.6 eggs/♀ for control congeners. Positive fecundity inhibition percentage values were recorded at low doses. Females exposed to the highest dose showed negative responses, irrespective of the period of treatment. The fertility was also found to be slightly affected, where it declined (88.4 and 83.5 vs. 95.8 % for control) for females treated with the higher doses (9.72X10 5 and 19.2 x 10 5) for 24 and 48 hours, respectively. Finally, the sterility index had been calculated and proved the detrimental effects of the mid and high doses on the egg hatchability.
This investigation documents the presence of the alien macroalgal species Rivularia atra Roth ex ... more This investigation documents the presence of the alien macroalgal species Rivularia atra Roth ex Bornet & Flahault (Rivulariaceae: Nostocales) and Polysiphonia opaca (C. Agardh) Moris & De Notaris (Rhodomelaceae: Ceramiales) for the first time on the Libyan coastline. Of 7 investigated sites along Al-Jabel Al-Akhdar coastline during summer 2013 and winter 2014, three sites were invaded by R. atra and one site by P. opaca. The percent cover and relative frequency – as measures of abundance-of R. atra (15-24% and 40-70% respectively) were higher than those of P. opaca (8% and 17 % respectively). The investigation revealed that R. atra and P. opaca inhabited not only the rocky substrates but also the limpet Patella caerulea and that the two species do not thrive in polluted habitats. Statistical analysis showed a highly significant effect of season, site and their interaction on the physico-chemical characteristics of water. The results concluded that the nature of substrate as well as the extent of pollution may be major modifiers of algal distribution, since the non-polluted bare rocky shore was the favorite habitat for the alien species R. atra and P. opaca. Therefore, these species are promising indicators for water quality.
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